Page 310 - Practical English Usage 3ed - Michael Swan, Oxford

-ing fonns (8): participles; progressive verbs 300
Sorry + infinitive is used to apologise for current situations - things that one is doing or going to do, or that one has just done.
Sorry to disturb you - could I speak to you for a moment? I'm sorry to tell you that you failed the exam.
Sorry to keep you waiting - we can start now.
15 certain and sure
Certain/sure of+ -ing are used to refer to the feelings of the person one is talking about.
Before the game she felt certain o f winning, but after a few minutes she realised it wasn't going to be so easy.
You seem very sure o f passing the exam. I hope you're right. Certain/sure + Infinitive refer to the speaker's or writer's own feelings.
The repairs are certain to cost more than you think. (NOT The repttirs are certain (7f e6S1:i11tf • • . )
Kroftova's sure to win - the other girl hasn't got a chance.
Note that He is sure to succeed means 'I am sure that he will succeed'.
16 interested
To talk about reactions to things one learns, interested + infinitive is commonly used.
I was interested to read in the paper that scientists have found out how to talk to whales.
I'm interested to see that Alice and Jake are going out together.
I shall be interested to see how long it lasts.
To talk about a wish to find out something, both interested + -ing and interested + infinitive are common.
I'm interested in finding out I to find out what she did with all that money.
Aren'tYOll interested in knowing I to know whether I'm pregnant?
To talk about a wish to do something, we use interested with an -ing fonn.
I'm interested in working in Switzerland. Do you know anybody who could help me? (NOT I'm illterestetl ttl WtJI'k in Swif%erlarttl ...)
300 -ing forms (8): participles; progressive verbs
1 a crying baby
We can use -ing forms as adjectives before nouns. I was woken by a crying baby.
There is growing anger at the government's policies.
When -ing fonns are used like this, they are called 'present participles'. Their use is explained in 408-410.
2 not knowing what to do ...
Participles can be used in another way. They can combine with other words into 'participle clauses'.
Not knowing what to do, I telephoned the police. Who's the girl dancing with your brother?
For details of participle clauses, see 411.
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